Contrivance for the simultaneous winding-up and unwinding of an endless film-strip



April 20, 1937. E LANGE 2,077,843

CONTRIVANCE FOR TIHE SIMULTANEOUS WINDING-UP AND UNWINDING OF AN ENDLESS FILM STRIP Filed March 22, 1933 5 Sheets-Sheet l A ril 20, 1937.

E. LANGE CONTRIVANCE FOR THE SIMULTANEOUS WINDING-UP AND UNWINDING OF AN ENDLESS FILM STRIP Filed March 22, 1933 5 Sheets-Shet 2 Aprll 20, 1937. E. LANGE 2,077,843

'' CONTRIVANCE FOR THE SIMULTANEOUS WINDING-UP AND UNWINDING OF AN ENDLESS FILM STRIP Filed March 22, 1953 3 Sheets-Sheet 5 fiz zzzz arz in" y Patented Apr. 20, 1937 PATENT OFFICE CONTRIVANCE FOR THE SIMTUL ANEOUS UNWIND WINDING-UP AND '1' ING OFAN ENDLESS FILM-STRIP I Emil Lange, Berlin-Zehlendorf, Germany Application March 22, 1933, Serial No. 662,131 In Germany March 23, 1932 2 Claims.

Endless cinematographic films in the form of loosely wound coils, and feeding devices for such films in the form of pairs of rollers adapted to clamp the coil convolutions in one portion of the coil firmly together and to maintain the convolutions in the remainder of the coil properly spaced and free for frictionless relative displacement, are already known.

In order to prevent the film from being scratched and worn, it is essential that the clamped film portions should be kept perfectly free from relative displacement, and this is not altogether possible with the use of feed rollers as just described, particularly if the film is of substantial length.

The object of the present invention is to obtain a feeding device bymeans of which endless films of any length can be fed in a perfectly satisfactory manner, and the invention consists in the employment of feeding elements in the form of endless, spring-pressed, travelling belts between which the film convolutions are clamped.

Fig. 1 of the accompanying drawings represents a diagrammatic view of a film-feeding device constructed according to the invention,

Fig. 2 is a view of a modification,

Fig. 3 is a sideview of one of the feeding elements,

Fig. 4 is a fragmentary plan view thereof, and

Fig. 5 is a. view of an open casing showing a modified coil-feeding arrangement.

The endless cinematographic film is formed into a loosely wound, annular coil one portion of which is according to the invention clamped between feeding elements in the form of endless, spring-pressed, travelling belts which impart to the coil the necessary feeding movement, the belts being arranged so that the coil portion engaged between them will be perfectly straight and so that relative displacement of the compressed and travelling film layers will be obviated. wing to the loose winding of the coil, the convolutions will, outside the reach of the feed belts, be in spaced relation to one another and free for frictionless relative displacement. In this manner an endless film of any desired length can be fed through a projection apparatus with very little wear.

The belts are preferably composed of plates 39 which are hinged together like chain links, as best shown in Fig. 4. The hinge pins 4I project from the ends of the plates and engage in notches 43 in the driving and supporting discs, the pins are also adapted to ride on the edges of laterally disposed guide plates 42. The belt at the outer side of the coil is controlled by springs 44 which press the belt to the coil and clamp it to the belt 40 which is rigidly supported. In order to main- -41 and 48 are supported and fed by means of two belts 49 and 50 the latter of which is controlled by springs 59 arranged to bear against a bridge 59 which connects two laterally disposed belt protecting plates 55. The latter are mounted on the shafts of driving discs 53 having notches for engagement with the hinge pins the latter being adapted to ride on the edges'of guide plates 52. In this case the film passes through the projection gate fromthe outside of one coil section to that of the other, and the inner coil convolutions 41a are subjected to a similar transfer in the opposite direction.

Instead of suspending the film coil in a vertical position, a coil may be placed horizontally on suitable supporting rollers. Such an arrangement is shown in Fig. 5. The casing 93a is provided with horizontally disposed rollers 93' whereon the film coil I00 is supported. The slits 94' and 95' through which the film 96 passes into and out of the casing are arranged one at the circumference of the casing and the other in the bottom wall thereof. The feeding device consists of endless belts I02 and I03, the latter of which is controlled by springs I04 and I05 as shown diagrammatically in the drawings. Driving shafts I06 and III! are fitted with bevelled pinions I08, I09, H0 and III for engagement with corresponding bevel gears mounted on the shafts ably feathered on the shafts so that they can follow the displacements to which the belt I03 is subjected by the springs. The driving shafts receive their motion by means of a chain I I2 from a sprocket wheel II4 mounted together with a driving pulley 99 on a shaft H3. The casing is provided with brackets 91, 98 .to which a lid can be hinged.

The external part of the film is preferably guided between endless bands of soft material mounted in the projector, and means are provided .of the belts. The pinions I08 and III are slidallowing the film to be brought by a movement in lateral direction, into and out of engagement with the driving and guiding elements of the projector so that no cutting of the endless film will be required.

I claim:-

1. A device for feeding loosely coiled, endless cinematographic films, comprising a pair of endless travelling belts composed of hingedly connected plates, supporting rollers for said belts, a support for said rollers, said rollers being relatively adjustable for admitting a portion of the film coil between the belts, means for driving the belts at the same linear speed, and springs acting on the rollers of one belt for clamping the belts to the admitted coil portions.

2. 'A device for feeding loosely coiled endless cinematographic films, comprising a pair of endless travelling belts, supporting rollers for said belts having notched edges, a support for said rollers, said rollers being relatively adjustable for admitting a portion of the film coil between the belts, springs acting on the rollers of one of the belts for clamping the latter to the admitted coil portion, each belt being composed of plates having hinge eyes, hinge pins connecting said plates by engagement with the eyes and having projecting ends adapted to engage in the notches of said rollers, means for imparting motion to the rollers so as to drive the belts at the same linear speed,

and plates arranged between the supporting rollers as guides for the pins.

EMIL LANGE. 

